Book Review: Amplifiers
Written by Peter Rodmell, our Don Field reviewed this title in November 2016
Author: Don Field, G3XTT
Peter Rodmell G3ZRS is recommended in Steve Ireland’s article as someone who can repair linear amplifiers. What he didn’t say is that Peter was the founder of Linear Amp UK Ltd and has, over the years, built and repaired literally thousands of amplifiers. Peter has now retired from the manufacturing business although the brand still lives on under the ownership of PW advertiser The DX Shop.
Following his retirement, Peter set out to document his years of learning and experience with regard to linear amplifiers as a book, recognising that no book existed covering this topic specifically. Although not a reader or writer, having only discovered late in life that he was dyslexic, Peter decided to self-publish.
He also decided to spare no expense in terms of illustrations – the book includes some excellent colour photographs of valves, complete amplifiers and more.
Amplifiers was first published in 2014 and runs to 303 pages. The chapter headings give a good idea of what is covered, including the history of valves and amplifiers, descriptions of many classic and current models (with circuit diagrams, photographs and some history), a chapter specifically on the popular Kenwood TL-922 (I could have done with that years ago – see my earlier musings!), an overview of the amplifiers manufactured by Linear Amp UK and a chapter each on how to build your own amplifier for VHF and HF respectively. There is some ancillary material in other chapters too.
The book is an easy read and Peter has an entertaining way with words, for example, “...my big gripe about the SB220 would be the helicopter fan on the back panel. It really sounds as if it wants to take off”. As an editor, I spotted a few typos but, given his self-declared dyslexia, Peter can certainly be forgiven that and it doesn’t detract from the overall effect.
I’ve never personally aspired to building a linear amplifier. The parts can be difficult to source and valve amplifiers have high voltages all over the place. Good protection circuits are potentially complex too. But I very much enjoyed reading about the valves and about the various amplifiers I have owned or wished I had owned.
This isn’t a book for every radio amateur because not every radio amateur has an interest in high power amplifiers. However, if you do, I would suggest it is a must for your bookshelf.
This review is taken from the November 2016 issue of Practical Wireless.